weighton



UNITED STATES PATENT OFFICE.

ROBERT LUNAN VEIGIITON, OF NEVCASTLELUPON-TYNE, AD DONALD BARNS MORISON,OF I-IARTLEPOOL, ENGLAND.

ENGINE HAVING TWOOR MORE CYLINDERS.

SPECIFICATION forming part of Letters Patent N o. 617,620, dated January10, 1899.

Y Application iiled December 22, 1897. Serial No. 662,987. (No model.)

T0 all whom it may concern: Y

Be it known that we, ROBERT LUNAN \VEIGHTON,residing at Newcastle-11pon-Tyne, in the county of Northumberland, and DON- ALD BAENs MoRIsoN,residing at Hartlepool, in the county of Durham, England, subjects ofthe Queen of Great Britain and Ireland, have invented Improvements inEngines Having TWO or More Cylinders, (for which I have obtained apatent in Great Britain, dated August 1l, 1896, No. 17,732,) of whichthe following is a specification.

Our invention has reference to improved constructions of engines inwhich particular arrangements and methods of balancing or relieving thevalves are adopted and in which` the valves of two or more cylindersworking upon two cranks are actuated by one set of valve-gear.

In the case of a steam-distribution valve of the flat or slide type fora cylinder of a multiple-expansion engine we so arrange thatsupply-steam is iirst admitted to the central portion of the valve, theinside edges of the valve constituting the admission and cut-off edgesand the outside edges the release and compression edges. The valve whenworking under steam is keptin contact With the valveseat on the cylinderby the action of extensions of the valve-face, which afford an increasedare'a to be acted upon by the steampressure in the receiver in which thevalve works. These extensions of the valve-face may be made either atthe ends or at the sides of the valve or in both directions, as may befound convenient in particular cases, and these extensions of the valveor the valveseat on the cylinder, or both, are or may be recessed on theface and such recesses connected by a pipe or pipes or otherwise, asfound convenient, to any suitable source of lower steam-pressure-c. g.,to another receiver of the engines, to the hot-well, the condenser, orthe atmosphere.

To assist in retaining the valve on its seat or to insure that it willreadily take its seat aft-er the engine starts, a spring or springs orother suitable means may be used, as found necessary or convenient.

The valve above described being a valve in equilibrium or a valverelieved from the load due to steam-pressure to any desired degree, itobviously may with advantage be used in any arrangement ofmultiple-expansion engines, independent of the nature of the valve-gearor of the angles at which the cranks are set. A

In the case of any two consecutive cylinders of multiple-expansionengines in which the exhaust-steam of the iirst cylinder is thesupply-steam of the second cylinder and which cylinders Work on'separate cranks, the valves being driven by one set of valve-gear, Wearrange valves of the flat or slide type back to back in a commonchamber or receiver. The valve of the first or higher-pressure cylinderis a valve of the type described in the iirst part of thisspecification, 'supplyp steam being first admitted to its centralportion, whence its distribution to the cylinder is governed by theinside edges of the valve, the exhaust taking place over its outsideedges into the containing-receiver and the valve being kept up to itsseat when working by means of the provisions already described. Thevalve of the second or lower-pressure cylinder is a iiat or slide valve,taking steam in the reverse manner from the iirst valve, the

outsideedges governing the admission and cut-off and the inside edgesthe release and compression. The two valves are suitably connectedtogether and are driven by means of one spindle andone set ofdriving-gear, and their relative positions may be adjusted andmaintained by a spring or springs or by other means, as may be foundnecessary or convenient, the steam passing from the iirst to the secondcylinder directly through the containing chamber or receiver, in whichboth valves work.

In order that our invention may be fully understood, we append twosheets of explanatory drawings, Figures l, 2, and 3 showing in verticalsection three various constructions of our balanced valve, and Figs.4and 5 showing in sectional elevation and sectional plan, respectively,an arrangement in which the valves of two consecutive cylinders aredriven by one set of valve-gear. Fig. (i illustrates in elevation amethod by which the valves illustrated in Figs. 4 and 5 are connected toenable them to be driven by one spindle and one set of valve-gear.

Referring to Fig. 1, the valve 1 is arranged with extensions 2 2, whichmay be provided with recesses 3 3, connected (by pipe or otherwise) toany source of lower pressurensuch as another receiver, the hot-well, orcondenser. lVe prefer that communication between the recesses 3 3 andthe source of lower pressure should be established by means of a passageformed through the valve-seat and a xed pipe connected thereto as, shownat 22, Fig. 5; but a passage might be formed for the same purposethrough the valve itself, the connecting-pipe in that case beingattached to the Valve so as to move with it and being arranged to workthrough stung-boxes where necessary. Recesses are here shown in thevalve-face only 5 but they may equally be formed in the valve-seat, orin both. Supplysteam is admitted through the passage 4 and port 4 to thecentral portion 5 of the valve I, the inside edges 6 6 forming theadmission and cut-off edges, and steam enters the cylinder 7 through theports 8 in' the usual manner. The release and compression are controlledby the outside edges 9 0, the exhaust taking place through the ports l()l0 into the chamber or receiver 7". It will be seen that by means oli'the extensions 2 2"l and other extensions, if any, the increased area ofthe valve I, acted upon by the steampressure in the receiver 7b, may beso arranged and adj usted that the valve is relieved or balanced to anydesired extent and retained in position on the valve-face 7.

Fig. 2 is a modiiication in which the extensions 2 2 are arrangedbetween the ports of the valve I, steam-supply being admitted throughthe passage l and port 4 to the inside portions 5 5, which correspondwith the central portion 5 in Fig. 1.

Fig. 3 is a further modification in which there is a single extension 2of the valve I, the inside portions 5 5 corresponding with the centralportion 5 in Fig. 1. Steam-supply is admitted through the passage t andports 4C 1b in the cylinder-face, these ports corresponding with theport 4 in Figs. 1 and 2.

Figs. 2 and 3 show two modications embodying this invention; but it isevident that various other modifications may be employed, depending onthe particular design of engine to which they may be applied. In Figs.1, 2, and 3 extensions are shown at the ends of the valves only. It is,however, obvious that the sides of the valves, as in Fig. 5, may be alsoextended and recessed to any degree necessary for the efiicient workingof the valve.

Fig. et shows an arrangement in which the valves of two consecutivecylinders of a multiple-expansion engine are driven by means of one setof valve-gear, the construction of the valve I of the first cylinder 7being simi lar to that described with reference to Fig. l, steamexhausting into the receiver 7b, whence the second cylinder draws itssupply. The second cylinder 12, with its ports 13 13 and valve-face 14,takes steam in the reverse man nerthat is to say, the outside edges 1515 of the valve 16 form the admission and cutoi edges, the inside edges17 17"l governing the release and compression, exhaust taking placethrough the central portion 1S and passage 19. The relative positions ofthe valves l and 16 are adjusted and maintained by springs 20 orothersuitable means, the single spindle 21 forming the driving-gear.

For the sake of clearness in the drawings we have shown the valves assingle-ported only; but it is obvious the ports may be increased to twoor more, as desired.

lVe wish it to be understood that we do not claim as our invention themere driving of two valves for two separate cylinders by one set ofvalvegear, nor do we claim a slidevalve so arranged as to take steaminto thc inside of the valveand exhaust it at the out side, as we areaware that both of these arrangements have been used; but

lVhat we do claim isl. The combination with a steam-cylinder having avalve-seat, and having passages 8, 8, from the ends of the cylinder toseparate points of the valve-seat, and a steam-inlet passage extendingto said valve-seat intermediate the iirst-mentioned passages, of a flatslide-valve on the valve-seat having outer parts 9, 9 controlling thepassages from the ends of the cylinder and having an intermediatechambercd part with edges 6, G controlling the connection of thesteam-inlet to passages S, S, said valve having extensions to increaseits area, and a steam-chamber inclosing the valve and into which steamfrom the' cylinder is exhausted.

2. The combination with a steam-cylinder having a valve-seat, and havingpassages 8, 8 from the ends of the cylinder to separate points of thevalve-seat, and a steam-inlet passage extending to said valve-seatintermediate the first-mentioned passages, of a slidevalve on thevalve-seat having outer parts 9, 9 controlling the passages from theends of the cylinder and having an intermediate chambered portion withedges 6, G controlling the-connection of the steam-inlet to passages 8,8, said valve having extensions to increase its area, said extensionsVor the valve-seat, or both being recessed on the working faces, aconnection from said recess or recesses to a source of lower pressure,and a steam-chamber inclosing the valve and into which the steam fromthe cylinder is exhausted.

The combination of two consecutive cylinders of a multiple-expansionengine having valve-seats, passages from the ends of the IOO names tothis specication in the presence of two subscribing Witnesses.

ROBERT LNAN WEIGHTON. DONALD RARNs-MORIsON.

Witnesses to the signature of the said Robert Lunan VVeighton:

HARRY BENSON, PEROY CORDES. lVitnesses to the signature of the saidDonald Barns Morison:

T. HARRY TILLY, J. BARRWELL STROVER.

In testimonywhereof We have signed our I5`

